1. Field of the Invention
The present invention relates to a technology for providing a projector apparatus.
2. Description of Related Art
The projector apparatus is adapted to modulate a light beam from a light source by means of a image display element such as a liquid crystal panel in response to an image signal so as to produce an optical image (the so-called picture image), and then to project the optical image onto a projection surface such as an outside screen or a wall surface by means of a projection lens or a projection mirror. These years, there have been prosperously used, as the projector apparatus, projectors in which the distance to the projection surface (projection display distance) can be extremely shortened in the case of projection onto the projection surface such as an outside screen (Refer to Patent Document 1 and Patent Document 2).
Patent Documents 1 and 2 disclose a projector apparatus in which, as shown, for example, in FIG. 1 in Patent Document 2, a display light beam having an image (optical image) which is produced through modulation in an image display element within a housing, in response to an image signal, is emitted from the housing through a light output opening of the housing, and is then reflected by a projection mirror standing upright on the outer wall surface of the housing so as to be enlarged and projected onto an outside projection surface. Further, when this projector apparatus is not used, the projection mirror is folded down onto the outer wall surface of the housing in order to cover the light output opening. With the configuration as stated above, since the projection mirror which serves as a part of the housing, can be pulled up so as to set up a projection optical system for the screen during the use thereof while the projection mirror can be folded down during no use thereof, the projector apparatus can be miniaturized as a whole, thereby it is possible to extremely facilitate the handing of the projector apparatus. Further, during no use thereof, since the opening can be covered by the projection mirror, it is possible to prevent invasion of dust.    Patent Document 1: JP-A-2005-141065    Patent Document 2: JP-A-11-119343
In the projector apparatus disclosed in Patent Document 1 or 2 as stated above, the projection mirror is pulled up so as to stand upright on the outer wall surface of the housing during the use thereof, being opened to a predetermined angle. Thus, for example, there would be possibly caused such a risk that the reflection surface of the projection mirror scratches or the position of the projection mirror is deviated from its adjusted set position, being caused by a turnover of the projector apparatus (as will be detailed later in this embodiment). Should the projection mirror have any scratch, this scratch would be reflected into a projected image. Further, should the position of the projection mirror be deviated from its adjusted set position, there would be caused a problem such as a positional deviation of a projected image or a defocus of the image. However, the above-mentioned Patent documents fail to take into sufficient consideration with the protection of the projection mirror against any breakage or damage thereof.
By the way, the arrangement in which the projector apparatus is set up is selected in accordance with a used condition such as a position where an image is projected or a direction of the projection, that is, either one of a permanent set-up arrangement, a suspension arrangement from a ceiling and a vertical arrangement (the so-called downward projection arrangement or desk-top arrangement) is selected. Among these set-up arrangements, in particular, the downward projection arrangement (the vertical arrangement or the desk-top arrangement) for inclining the direction of image projection downward, would possibly cause the projector apparatus to be unexpectedly turned over by the user since the gravitational center of the apparatus becomes unstable (will be detailed later in this embodiment).
Further, there would possibly be caused such a failure that the projector apparatus is accidentally turned over when the projector apparatus is displaced. That is, in the conventional technology, there would be possibly caused such a problem that the projection mirror is broken or damaged due to a turnover of the projection apparatus due to erroneous handling of thereof by the user.